1. Field of the Invention
The present invention relates to an active matrix type display device using light-emitting elements in pixels, respectively, and a method of manufacturing the same. More specifically, the invention relates to a technique for improving a power source wiring formed in a panel constituting a display device.
2. Description of the Related Art
In recent years, a plane self-emitting type display device using organic EL devices as light-emitting elements has been actively developed. The organic EL device is a device utilizing a phenomenon that when an electric field is applied across an organic thin film, the organic thin film emits a light. The organic EL device consumes less power because it is driven with an applied voltage of 10 V or less. In addition, the organic EL device needs no illumination member, and thus the light weighting and thinning thereof are readily realized because the organic EL device is a self-emitting element for emitting a light by itself. Moreover, the organic EL device operates at a very high speed because of its high response speed of several micro seconds. Thus, no afterimage in a phase of display of a moving picture occurs.
Of the plane self-emitting type display devices using organic EL devices in the pixels, respectively, especially, an active matrix type display device in which thin film transistors are formed as drive elements integrally with one another in each pixel has been actively developed. The active matrix type plane self-emitting display device, is described for example, in Japanese Patent Laid-Open Nos. 2003-255856, 2003-271095, 2004-133240, 2004-029791, and 2004-093682.